This invention relates to network shelf systems, which are used to support networking equipment and to provide mounts for patch panels for interconnecting communication cables.
Telephone and data cables in a building, for example, interconnect telephone handsets and computer terminals located at desks and offices throughout the building with each other and with centralized communication facilities, including trunk lines, network servers, and PBX equipment. To permit flexibility in configuring and later changing the interconnections, cables are run from each telephone, computer, truckline, PBX, server, and other device, to a central interconnection "closet". The end of each wire of a cable is connected to terminals in a punch down block, which is commonly part of a patch panel. The terminals of the punch down block are in turn tied to accessible modular connectors. The final interconnection of cables is then achieved by short cables run between selected pairs of the connectors. To reconfigure the interconnection scheme, the user simply disconnects and reconnects the short cables to other pairs of the connectors.
Setting up an interconnection closet is a labor intensive activity. Typically, there are a large number of patch panels. The many hundreds of wires in the cables routed to the closet must be individually punched down into the blocks. Then, the patch panels must be individually mounted on a rack or in a cabinet often using screws.
Occasionally a new cable is run into the closet and must be punched down to one of the blocks. This requires that the installer have access to the back of the blocks where the punching down is done.
Various wall mounted patch panel devices have been configured to attempt to allow an installer to have ready access to the back of their punch down blocks. These configurations typically include hinges, which allow the patch panel to swing left to right or top to bottom to give access to the back of the panel. Both of these arrangements require careful cable management to prevent excessive stresses on the attached wires. Also, since punching down typically requires an installer to apply substantial forces in order to punch down a wire or cable, many patch panels are, or must be, configured to be removed from a rack or a wall to another location (e.g., a table), which is able to support the panel against the forces exerted during punching down. An alternate arrangement, which is taught in U.S. Pat. No. 5,401,193 (Lo Cicero et al.), is a Patch Panel System, which includes a support shelf against which a hinged patch panel is supported to allow an installer to readily apply the necessary forces to punch down a connection. However, a significant drawback of the Lo Cicero Patch Panel System is that it requires an installer to be physically located at an elevation above the patch panel system in order to apply forces against the support shelf when punching down connections. Thus, the Lo Cicero Patch Panel System can only be used in relatively low locations. Accordingly, a drawback of Lo Cicero and other patch panel systems is that they cannot be stacked up to the ceiling level and still be readily accessible by an installer.